Veteran MP George Galloway has said the Scottish independence referendum should include a second question calling for more devolved powers instead of secession.

The Dundee-born politician, a former Labour MP who returned to Westminster under his Respect platform in the Bradford West by-election in March, said he opposes independence but backs a second question on "full economic powers short of secession".

First Minister Alex Salmond has not ruled out including a second referendum question on greater economic powers for the Scottish Parliament for those who vote No to independence, commonly described as devo-plus or devo-max.

"Alex Salmond, until recently a consummate operator, has sullied himself and surely damaged his party in the polls with the leaked emails about kissing and not telling with (media tycoon Rupert) Murdoch. When you trawl the gutter, you harvest the filth.

"But where we do agree, and I thought I'd never say this, is on the economy."

The left winger said the Tory-Lib Dem coalition at Westminster has been a "soaring failure" on the economy and said his former Labour stablemates' "clothes have been stolen" by the SNP in Scotland with its "popular social democratic" policies.

Galloway said: The Scottish Government needs power over the economy, pulling the levers for the worthy rather than the wealthy, which is why I favour a second question option on the ballot paper, however it's phrased and whatever it's called.

"Devo-max? Independence-lite? However it's described, it should be full economic powers short of secession."